21 lines
582 B
Markdown
21 lines
582 B
Markdown
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title: Binomial Distribution
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---
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If X ~ B(n,p) then:
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P(X=x) = (n/x)p^x multiplied by (1-p)^(n-x)
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If X ~ B(n,p) then:
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E(X) = np
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Var(X) = np(1-p)
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Binomial distributions only occur if:
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- There's a fixed number of trials, n.
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- Each trial should be either a success or failure.
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- Probability of success (p) is constant at each trial.
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- Independent trials.
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